BEGIN; BEGIN EXPLAIN (ANALYZE, BUFFERS) select n_name, sum(l_extendedprice * (1 - l_discount)) as revenue from customer, orders, lineitem, supplier, nation, region where c_custkey = o_custkey and l_orderkey = o_orderkey and l_suppkey = s_suppkey and c_nationkey = s_nationkey and s_nationkey = n_nationkey and n_regionkey = r_regionkey and r_name = 'AFRICA' and o_orderdate >= date '1995-01-01' and o_orderdate < date '1995-01-01' + interval '1 year' group by n_name order by revenue desc; QUERY PLAN ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Sort (cost=1979045.49..1979045.56 rows=25 width=34) (actual time=16633.607..16633.608 rows=5 loops=1) Sort Key: (sum((lineitem.l_extendedprice * (1::double precision - lineitem.l_discount)))) Sort Method: quicksort Memory: 25kB Buffers: shared hit=2371986 read=369914 written=1005 -> HashAggregate (cost=1979044.66..1979044.91 rows=25 width=34) (actual time=16633.563..16633.564 rows=5 loops=1) Group Key: nation.n_name Buffers: shared hit=2371983 read=369914 written=1005 -> Hash Join (cost=105692.66..1978311.27 rows=73339 width=34) (actual time=2216.672..16547.744 rows=72260 loops=1) Hash Cond: ((lineitem.l_suppkey = supplier.s_suppkey) AND (customer.c_nationkey = supplier.s_nationkey)) Buffers: shared hit=2371983 read=369914 written=1005 -> Nested Loop (cost=101013.66..1959125.43 rows=1836461 width=46) (actual time=2152.111..15727.710 rows=1820177 loops=1) Buffers: shared hit=2369801 read=369914 written=1005 -> Hash Join (cost=101013.09..494890.58 rows=459221 width=38) (actual time=2152.091..8275.621 rows=454869 loops=1) Hash Cond: (orders.o_custkey = customer.c_custkey) Buffers: shared hit=413626 read=19344 written=74 -> Bitmap Heap Scan on orders (cost=62671.46..443346.34 rows=2296107 width=8) (actual time=27.574..5125.295 rows=2275103 loops=1) Recheck Cond: (o_orderdate >= '1995-01-01'::date) Rows Removed by Index Recheck: 6834341 Filter: (o_orderdate < '1996-01-01 00:00:00'::timestamp without time zone) Rows Removed by Filter: 5890556 Heap Blocks: lossy=256560 Buffers: shared hit=237229 read=19342 written=74 -> Bitmap Index Scan on orders_o_orderkey_o_orderdate_brin_idx (cost=0.00..62097.44 rows=8274325 width=0) (actual time=27.410..27.410 rows=2566400 loops=1) Index Cond: (o_orderdate >= '1995-01-01'::date) Buffers: shared hit=11 -> Hash (cost=34591.63..34591.63 rows=300000 width=38) (actual time=2122.086..2122.086 rows=299493 loops=1) Buckets: 524288 Batches: 1 Memory Usage: 25155kB Buffers: shared hit=176397 read=2 -> Nested Loop (cost=765.14..34591.63 rows=300000 width=38) (actual time=4.288..2008.464 rows=299493 loops=1) Buffers: shared hit=176397 read=2 -> Nested Loop (cost=0.14..13.95 rows=5 width=30) (actual time=0.028..0.080 rows=5 loops=1) Join Filter: (nation.n_regionkey = region.r_regionkey) Rows Removed by Join Filter: 20 Buffers: shared hit=3 -> Index Scan using pk_nation on nation (cost=0.14..12.51 rows=25 width=34) (actual time=0.006..0.023 rows=25 loops=1) Buffers: shared hit=2 -> Materialize (cost=0.00..1.07 rows=1 width=4) (actual time=0.001..0.001 rows=1 loops=25) Buffers: shared hit=1 -> Seq Scan on region (cost=0.00..1.06 rows=1 width=4) (actual time=0.009..0.013 rows=1 loops=1) Filter: (r_name = 'AFRICA'::bpchar) Rows Removed by Filter: 4 Buffers: shared hit=1 -> Bitmap Heap Scan on customer (cost=765.00..6315.54 rows=60000 width=8) (actual time=4.298..391.838 rows=59899 loops=5) Recheck Cond: (c_nationkey = nation.n_nationkey) Rows Removed by Index Recheck: 1440101 Heap Blocks: lossy=176390 Buffers: shared hit=176394 read=2 -> Bitmap Index Scan on customer_c_nationkey_c_custkey_brin_idx (cost=0.00..750.00 rows=60000 width=0) (actual time=4.264..4.264 rows=353280 loops=5) Index Cond: (c_nationkey = nation.n_nationkey) Buffers: shared hit=4 read=2 -> Index Scan using pk_lineitem on lineitem (cost=0.56..3.04 rows=15 width=16) (actual time=0.013..0.015 rows=4 loops=454869) Index Cond: (l_orderkey = orders.o_orderkey) Buffers: shared hit=1956175 read=350570 written=931 -> Hash (cost=3179.00..3179.00 rows=100000 width=8) (actual time=63.936..63.936 rows=100000 loops=1) Buckets: 131072 Batches: 1 Memory Usage: 4931kB Buffers: shared hit=2179 -> Seq Scan on supplier (cost=0.00..3179.00 rows=100000 width=8) (actual time=0.007..37.973 rows=100000 loops=1) Buffers: shared hit=2179 Planning time: 5.309 ms Execution time: 16634.394 ms (60 rows) COMMIT; COMMIT